The priority application claims priority of Japanese Patent Application No. 2004-147165, which is hereby incorporated by reference.
1. Field of the Invention
This invention relates to a head-up display device. In more detail, this invention relates to a head-up display device allowing a position of an projected image to be easy adjusted after the head-up display device is mounted on an instrument panel of a vehicle, and presenting a good appearance.
2. Description of the Related Art
FIG. 6 shows a schematic view showing a configuration of a conventional head-up display device (HUD). As shown in FIG. 6, the head-up display device 1 includes a housing 2, a display unit 3 attached to the housing 2, a first mirror 4, a front pane 5, a second mirror 6, a reflector 7, and a cover 8. A projected image 9 is emitted from a surface of the display unit 3 fixed on a bottom of the housing 2. Then, the projected image 9 is reflected by the first and second mirrors 4, 6. Then, the projected image 9 passes through an opening 2a opened on an upper wall of the housing 2, and is further reflected by the reflector 7. Then, the projected image 9 reaches an eye point 10 in an eye range of a vehicle driver.
For improving visibility of the projected image 9, the projected image 9 emitted from the display unit 3 is reflected and magnified by the reflector 7. Therefore, dimension and angle errors of optical parts are also magnified to affect the projected image 9 considerably. For preventing the errors, for example, all the optical parts are fixed on the housing 2 made of a rigid frame.
FIG. 7 shows an embodiment of the conventional head-up display device mounted on an instrument panel 20 of a vehicle. The head-up display device 1 is fixed on the instrument panel 20, and an instrument panel cover 21 covers a periphery of the head-up display device 1. As shown in. FIG. 8A, an upper wall of the cover 8 of the head-up display device 1 is so positioned to be flush with a surface of the instrument panel 20 when the cover 8 is closed. The large instrument panel 20 is made of synthetic resin. Therefore, tolerance of the instrument panel 20 is much larger than that of the head-up display device 1.
Accordingly, because the tolerance of the instrument panel 20, on which the head-up display device 1 is mounted, is large, even if the tolerance of the head-up display device 1 is reduced, the projected image 9 may be misaligned or tilted. For preventing the misalignment or the tilt, an angle adjustment mechanism is attached to a position where the head-up display device 1 is mounted on the instrument panel 20 for adjusting an angle of the mounted head-up display device 1. Thus, an erect image of the projected image 9 is obtained without any tilt.
However, in some cases, the head-up display device 1 is tilted, and the upper wall of the closed cover 8 is not flush with the surface of the instrument panel as shown in FIG. 8B. When the head-up display device 1 is tilted, a large gap exists between the surface of the instrument panel 20 and the head-up display device 1. Therefore, there is a problem that an appearance of the instrument panel 20 on which head-up display device 1 is mounted becomes worse.
Accordingly, it is an object of the present invention to provide a head-up display device that allows a position of a projected image to be adjusted easily after the head-up display device is mounted on an instrument panel of a vehicle, and presents a good appearance.